A rationale for the set of theoretical and methodological techniques of mapping and deep modeling in the Russian Arctic shelf and adjacent sedimentary basins in continental Russia is based on the materials for the Barents and Kara Seas region. This article provides the factual basis of the research and shows how to apply zonal-block model of the crust and generalized models of geodynamic settings in terms of the different geophysical data inconsistency. The necessity and approach for global and regional paleo-reconstructions are also discussed. It is shown that localization of the principal structural and compositional units of the lithosphere being a consequence of geodynamic processes at the boundaries of lithospheric plates, form at the basis of sedimentary cover and crystalline basement layered maps as well as cross-sections of the continental crust. The identified parameters of the deep structure and milestones of the regional tectonic history open new opportunities to explore the regularities of ore deposits distribution. The shown example of the forecast and metallogeny problems solution within Western Siberia and Khatanga-Vilyui petroleum provinces is made using the parameters of known industrial oil and gas fields for training the pattern recognition system.
Possibilities of seismic methods of reflected and refracted waves have been examined for the purposes of detailed study on crystalline basement structure. Investigation of depth and structure of the basement plays an important role in the exploration of various deposits. Sedimentary cover is usually associated with oil and gas reserves. Ore deposits are formed in the basement rocks, basement splits and structure of its surface have a genetic relation not only to ore minerals, but also to oil resources. Reflection seismology is one of the main seismic methods of investigating structural geometry of the sedimentation mass, forecasting its material composition and possible hydrocarbon reserves. However, its possibilities for investigating crystalline basement are limited. Basing on many years’ experience of reflection seismology and physical modeling it has been identified that actual roughness of basement surface limits the obtainable amount of waves reflected from it. Possibilities of reflection seismology for basement structure study are mostly related to investigation of discontinuous faults as diffraction objects using diffracted waves. Method of refracted waves combined with modern procedures and material processing aimed at getting dynamic seismic sections holds much significance for the basement study, especially in the process of surface mapping and, to a lesser extent, in investigating discontinuous faults. Combining seismic methods of reflected and refracted waves in basement study increases reliability of forecasting its geological structure: in particular, its surface can be well defined by means of refraction seismology, and zones of discontinuous faults are identified from diffraction objects using both reflection and refraction methods. As a result of applying both reflection and refraction seismology, an opportunity arises to carry out detailed analysis of basement structure and to predict its oil and gas content.
Bring the general scheme of processing including six operations which will transform field seismic recordings to change of elastic properties of the studied geological environment. Considered physical appointment and necessity of performance of each operation of processing. At the expense of recurrence of performance of four operations (the account of influence upper part of section, definition of speeds, easing of hindrances and increase detectability records) is formed a real processing graph of materials.
The main requirements for the shallow seismic field works technique parameters for engineer-geological issues solving are represented. The optimum technique for the St.-Petersburg and its suburbs territory based on the results of experimental seismic studies, providing a detailed study of the upper part of the geological section, are proved.
The article describes a new methodology for processing seismic data using the refracted-wave method. All seismic data are proposed to be processed on the basis of record migration (studying velocities at boundaries and in bedrock, recording displacements, and isolating useful events). The migration process involves wave imaging of all refracted boundaries of any shape using the kinematic and dynamic properties of the refracted waves. The result of data processing is a dynamic seismic section, similar to the section of the reflected wave method. Its geological interpretation uses not only kinematic but also dynamic properties of refracted waves. This makes it possible to predict not only the structural plan of deposits, but also their rock composition. The proposed method of processing has been tested both on model data and on real data of seismic refraction waves on the geophysical profile in the Barents Sea and on the Caspian Sea shelf. Examples are given of the processing of refracted wave data compared to the reflected wave section.
Сейсморазведочные работы МОВ , проведенные в Ленингорском и Березовско-Белоусовском районах Рудного Алтая в 1985-1986 гг., явилась первым опытом многократного профилирования в этом регионе. В статье рассмотрены особенности методики полевых работ и графа обрабатывающих процедур применительно к сейсмогеологическим условиям Лениногорского рудного поля ...